Fix PHP notices and warning

Author: technicalguru

src/TgLog/Log.php

@@ -326,7 +326,7 @@ public static function clean() {
 	 * @return array list of messages registered.
 	 */
 	public static function get() {
-		return $_SESSION['messages'];
+		return isset($_SESSION['messages']) ? $_SESSION['messages'] : array();
 	}
 
 	/**

src/TgUtils/Date.php

@@ -263,7 +263,7 @@ public function calendar($format, $local = false, $translate = true) {
 	 * @return  string   The date string in the specified format format.
 	 *
 	 */
-	public function format($format, $local = false, $translate = true, $language = null) {
+	public function format($format, $local = false, $translate = true, $language = null):string {
 		if ($translate) {
 			// Do string replacements for date format options that can be translated.
 			$format = preg_replace('/(^|[^\\\])D/', "\\1" . self::DAY_ABBR, $format);
@@ -366,7 +366,7 @@ public function monthToString($month, $abbr = false, $language = null) {
 	 *
 	 * @note    This method can't be type hinted due to a PHP bug: https://bugs.php.net/bug.php?id=61483
 	 */
-	public function setTimezone($tz) {
+	public function setTimezone($tz):\DateTime {
 		$this->tz = $tz;
 
 		return parent::setTimezone($tz);
@@ -415,7 +415,7 @@ public function toUnix() {
 	}
 
 	/** create a local instance from given format */
-	public static function createFromFormat($format, $timeString, $timezone = null) {
+	public static function createFromFormat($format, $timeString, $timezone = null):\DateTime|false {
 		if ($timezone == null) {
 			$timezone = new \DateTimeZone(date_default_timezone_get());
 		}

src/TgUtils/Request.php

@@ -321,7 +321,7 @@ protected function initDocumentRoot() {
 	 */
 	protected function initOriginalPath() {
 		$rc = $this->path;
-		$rootDef = $_SERVER['HTTP_X_FORWARDED_ROOT'];
+		$rootDef = isset($_SERVER['HTTP_X_FORWARDED_ROOT']) ? $_SERVER['HTTP_X_FORWARDED_ROOT'] : '';
 		if ($rootDef) {
 			$arr = explode(',', $rootDef);
 			if (strpos($rc, $arr[0]) === 0) {
@@ -353,7 +353,7 @@ protected function initOriginalUri() {
 	 */
 	protected function initWebRoot($considerForwarding = TRUE) {
 		if ($considerForwarding) {
-			$rootDef = $_SERVER['HTTP_X_FORWARDED_ROOT'];
+			$rootDef = isset($_SERVER['HTTP_X_FORWARDED_ROOT']) ? $_SERVER['HTTP_X_FORWARDED_ROOT'] : '';
 			if ($rootDef) {
 				$arr = explode(',', $rootDef);
 				$rc = $arr[1];